One of the earliest references that Supernatural makes to The Simpsons is actually the perfect representation of the show's protagonists in its earlier seasons. Supernatural's 15-season run naturally saw its protagonists, the demon-hunting Winchester brothers, undergo a great deal of character development. Over the course of Supernatural's 15 seasons, Sam and Dean grow from young and relatively naive hunters to hardened and renowned veterans who regularly find themselves standing between humanity and the forces of evil.

Supernatural's early seasons remain beloved for a number of reasons. Season 1 of the show boasts one of Supernatural's scariest episodes, "Bloody Mary", and it also established a significant portion of the winning dynamic between Sam and Dean that carried the show through its long and successful run. It also set the tone for the entire series, a tradition that included dropping amusing and relevant references to elements of pop culture.

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One such reference comes in season 1, episode 18, "Something Wicked", in which Sam and Dean find themselves on the trail of a Shtriga, a witch that feeds on the life force of children. When listing the places that the Shtriga has previously been, Sam lists the towns "Brockway", "North Haverbrook", and "Ogdenville". These are the same towns that feature in an early episode of The Simpsons, "Marge vs. the Monorail": they are the three towns that con-man Lyle Lanley has previously sold monorails to. It's an incredibly subtle reference, and it's fitting, too - Lyle Lanley shares a number of similarities with Sam and Dean Winchester in Supernatural's early seasons.

Supernatural's Marge Vs The Monorail Reference Fits Its Early Seasons

Jared Padalecki as Sam and Jensen Ackles as Dean look at something in the pilot episode of Supernatural

The way that Supernatural characterizes Sam and Dean in its early seasons was eventually lost throughout the show's run as its narrative moved on, and the characters grew in notoriety among other hunters, demons, and supernatural creatures alike. However, early on, the pair were essentially little more than traveling con-men, not unlike Lyle Lanley in The Simpsons. Lanley is shown to be one of The Simpsons' smartest characters early on, deceiving the entire town of Springfield into believing the fantastical ideals he presents to them. This creates a key parallel between the memorable Simpsons character and the Winchester brothers, making the reference a clever nod to the way the characters often behaved.

Of course, as Supernatural's story developed, the gimmick of Sam and Dean taking on roles to deceive local authorities was used decidedly less. However, in its early seasons (particularly season 1, when the reference was made), this was something that happened in practically every episode, making the Simpsons reference particularly fitting. As it's a subtle and easy-to-miss reference, catching it is inherently rewarding, but it also speaks to the actual character of Supernatural's Sam and Dean, alluding to their talent for deception and likening them to The Simpsons' Lyle Lanley.